I am currently creating a character for 3d printing, but when I try to join to intersecting parts with boolean modifier, strange patterns appear over the targeted mesh. The patterns shift around and glitch when navigating the viewport, and nothing changes when the modifier is applied (it doesn't seem to actually unify the mesh either)
(Modifier on cloak, targeting body)
(Modifier on body, targeting cloak)
It is not just these two meshes, it happens with any two intersecting meshes on this model.
Note that all of the meshes are manifold and have similar mesh resolution.
The only other post on this issue I found was a similar unanswered question from 8 months ago on here - Boolean union not working properly
This is my first time creating a character for this purpose, so any help with how to fix this or alternatives would be appreciated. :)